Hi Tessa,
Just as a follow-up to others reading this thread, Tessa and I have looked into this and found that there is a bug in 3dDeconvolve when using -stim_times_IM for a regressor class that has no events. It is not such an odd case - one can see the use of IM in the case of missing or incorrect reponses, say, and then imagine that for some subjects, there might not be any such events. Having no events is fine for other cases, like -stim_times or -stim_times_AM2, but there are problems with -stim_times_IM.
We will look at what might be going on here. More news at some point...
Thanks a lot, Tessa!
- rick
